As an information and communication technology is developed and the utilization thereof is diversified, an application of an high-speed large-capacity information transmission technology based on optical communication is widely spreading not only in telecommunication covering several tens to several hundreds of kilometers but also in a field of data communication within several tens of meters. Recently, even in an ultra short range of several meters to several centimeters such as information transmission between a computer and peripherals, signal transmission for high resolution display devices, and signal transmission between boards in mobile devices, the necessity of an application of a high-speed large-capacity data communication technology is getting focused. Therefore, the integration and the cost reduction of an optical transceiver module are becoming an important technological issue.
As representative technologies that cope with the steeply increased demand for an information transmission technology based on optical communication in a data communication regime, a time-division multiplexing technology that improves an optical signal transmission rate per channel and a parallel optics technology to which several strands of optical fiber lines are applied are suggested. However, the increase in the number of optical fiber lines causes the increase in volume of the optical transceiver module, which negatively affects the module integration.
In the meantime, in an optical transmission system for a user access network according to a related art, a bidirectional optical transceiver module in which two different wavelengths are applied respectively to upstream and downstream of the same optical fiber line is considered as an important technical factor in the view of integration and cost reduction. A module which is configured by applying the method is usually referred to as a bidirectional optical subassembly (BOSA) or a BiDi module.
FIG. 1 is a view illustrating a general configuration of a BiDi module according to a related art.
Referring to FIG. 1, the BiDi module according to a related art includes an optical fiber 101, an optical filter 103, a light source element 105, and a light receiving element 107. The optical filter 103 assigns different optical paths to a transmitted light component and a received light component having respective wavelengths λ1 and λ2 and the light source element 105 and the light receiving element 107 which are formed as TO-can package shapes are arranged with an angle of 90 degrees to each other with reference to the optical filter 103.
For the purpose of integration and cost reduction of the optical transceiver module for high-speed large-capacity data communication, a configuration principle of the BiDi module in FIG. 1 may be applied. In this case, it is possible to reduce the number of transmission lines of the optical transceiver module by half. However, in the case of the configuration based on the TO-can package, there is still limitation on the integration of the module. Considering also that distances between the light source element and a driver IC and between the light receiving element and an amplifier IC need to be short for optical signal transmission at a high bit rate of 10 Gbps or higher, the configuration needs to be improved essentially. Furthermore, when an optical fiber array is applied in order to adapt the necessity of the large-capacity information transmission by getting away from a two-dimensional structure of the BiDi module of the related art, a structure of an optical transceiver module which is capable of efficient optical coupling and alignment is required.